Presently, a sealed button (FIGS. 1,2) comprises of an elastic spring (2) and a button (3). The elastic spring (2) is a section of thick steel line; and it is bent into an appropriate shape as an arc. Both ends of said elastic spring extended from the arc are as two straight strings (4) that are perpendicular to each other. The ends of the elastic spring (4) have a passive hook (6) and an active hook (7) that are used to button up inside the body (5) of the button (3). The button (3) is composed of a body (5) and a transparent cover (8). The body (5) is an one-side opening circular shell. Inside the body (5), there are the main guided slot (9) and the slant guided slot (10) perpendicular to each other. A button-up space (11) is extended from the rear end of the main guided slot (9); a positioning channel (12) that is installed on the corresponding wall of the of the button-up space (11); the main guided slot (9) and the slant guided slot (10) are used to guide the passive hook (6) and the active hook (7) to button up in position in the button-up space (11). The cover (8) is made to cover the opening of the body (5), and it must be made by transparent material. In order to identify, an identified device (13) is engraved in the back side of the cover (8). In this way, said identified device (13) can not be destroyed or changed by other people. Because of the wholly or partially opening of all the main guided slot (9), the slant guided slot (10) and the button-up space, the shapes of the passive hook (6) and the active hook (7) of the elastic spring (2) and the forming state after buttoning up could be apparently observed through the transparent cover (8). Therefore, such kind of a sealed button lacks secretiveness and security.